The present invention relates to solid forms of (1 r,4r)-6'-fluoro-N,N-dimethyl-4-phenyl-4',9'- dihydro-3'H-spiro[cyclohexane-1,1'-pyrano[3,4,b]indol]-4-amine hydrochloride, in particular crystalline forms and/or amorphous forms thereof, pharmaceutical compositions and medicaments comprising these solid forms, the use of these solid forms as well as to a process for obtaining them.